For most gamers, any discussion about Call of Duty starts and ends with multiplayer, but Call of Duty: Black Ops features a surprisingly competent single-player campaign that features the most cohesive CoD narrative yet.

Call of Duty: Black Ops' core plot isn't nearly as original or as inventive as it could have been, relying as it does on several well-worn twists 'borrowed' from various movies, and it suffers from a few issues. Certain plot points are clumsily handled; there are still moments where you have to brute-force your way to a checkpoint to trigger the next area; and they beat you over the head with the final reveal, as if they didn't trust the average gamer to understand what was going on.

Still, Call of Duty: Black Ops is a solid effort overall whose tone and spirit adequately captures the culture of paranoia that resulted from the tense 60s era cold war between the United States and Russia, the Cuban missile crisis, and the Vietnam War. The superior voice acting and motion capture work make it easy to enjoy the seven to eight hour story as it unfolds. It's especially worth playing because it unlocks a neat little surprise that's a nice bit of fan service.

Call of Duty: Black Ops multiplayer options

The term 'fan service' is also a good way to describe the approach Treyarch took with Call of Duty: Black Ops' multiplayer modes: it's obvious that the developers set out to make this installment the definitive online Call of Duty experience, and it helps that such a solid framework had been laid by the previous titles. All the expected mutliplayer modes are here - Team Deathmatch, Domination, Search and Destroy, Headquarters and so on - and for the most part, they play exactly as you'd expect, with the new map layouts, weapons, and perks having a strong effect on strategy and game flow.

The new Nova 6 grenade is a useful piece of equipment in any online mode with set capture points like Sabotage (Xbox 360 version)

For instance, the new Nova 6 grenade saturates an area with a nerve gas that disorients players and slowly saps health, rendering it a useful item to have in modes involving set capture points. Perks have also been reordered - Marathon, for example, is now tiered with Ninja, meaning you have to pick one or the other, putting an end to one of my favourite, albeit abused, perk combinations. Treyarch also brings back is popular Zombie mode, which will no doubt please gamers who enjoyed it in World at War. I was dismayed, however, that they chose to remove the highly underrated Spec-Ops mode from Call of Duty: Black Ops, and I sincerely hope it's offered down the line as a DLC add-on.

But the biggest tweak to the multiplayer is, of course, the currency system, which replaces XP in terms of unlocking weapons and attachments. Everything in the game, from perks to equipment, has to be purchased, and while the periodic feeling of hitting a jackpot found in previous CoD games is gone - DING DING DING, here's another trinket! - the currency system makes it easier for established fans to customise their gear to their liking.

You still have to achieve leveling milestones to unlock specific items in Call of Duty: Black Ops, but you don't have to grind levels just to get a silencer or a scope - you just dip into your bank account and purchase it outright. It's a sensible evolution because most gamers have logged enough online hours to know what their preferences are, so empowering them to customise their loadout makes a lot of sense.

The new Wager Matches are an interesting twist as well, letting you bet credits against your own performance; rank in the top three and you earn credits, rank anywhere else and you lose credits. These matches will no doubt be dominated by high level players the way poker games are usually dominated by card sharks, but even amateur gamblers can have fun thanks to the three tiers of betting. The lowest tier, Ante Up, only requires a 10 credit buy in, which is a modest enough entry fee to entice anyone to give it a try; the modes themselves are fun, with One in the Chamber and Gun Game topping my own personal list, and even though I never felt particularly thrilled by the gambling aspect, ending a round 'in the money' does lend a nice element of accomplishment to the experience.

Call of Duty: Black Ops extras

Treyarch also included a lot of extras that round out the overall experience and helps bring CoD up to date with contemporary franchises such as Halo. Theater mode, for example, isn't anything new, but it is smartly implemented, with each kill and death mapped as bookmarks on the timeline, letting you easily warp to a moment of triumph or defeat. Combat Training is also a worthwhile addition, especially for anyone who's been afraid to jump into the snarky, chaotic online environment; it's a closed environment where you can set up matches with your friends and bots to familiarise yourself with competitive play.

I was disappointed to find that Team Deathmatch and Free-for-All were the only modes available, but the bots do a decent job of replicating some of the behaviour you often see online - sniper camping, for instance. I also have to mention the character customisation features like emblems and clan tags as well as the ability to set up private matches with custom settings that the hardcore online community will no doubt appreciate.

This polished refinement of the Call of Duty formula offers a bevy of content that covers almost every expected base. Single-player campaign is satisfying, and the multiplayer has enough depth to keep fans engaged for a long time. But the single-player plot can be clumsy at times and they still haven't completely eliminated those taxing moments where you have to throw lives away just to reach a specific checkpoint (they are relatively rare this time around, though).